As to O2 enrichment, O2 is considered a waste product of photosynthesis, right? So why would anyone want to enrich O2 at all? I see no credibility to the notion. Does a plant uptake O2? I thought they only took up CO2 via stomata, and H2O with micronutirents etc via the root system. The idea of CO2 enrichment I can understand, but O2??, nah, I don't think so.
You can tell I only have a undergraduate's understanding of the process. As I have gotten older I realize much of what they taught us in school was simplified for ease of teaching and only has a passing likeness to the way stuff really happens. *G*
TIA,
K Barrett N Calif, USA
K,
Your notions about the destructive effect hydrogen peroxide has on cell
membranes is correct; the free radical components of H2O2 are highly
reactive, however they will seek out the protein receptors in the cell
membranes of bacteria and react to completion long before they can do any
serious damage to the much stronger plant tissue cell walls (keep in mind
that this is a 3% soln). As for paraquat... completely different animal,
this is a combination of organic molecules which effectively shut down plant
respiration through many different reactions.
I am intrigued by the prospect of improving plant tissue generation in
chemical rich environments, although I'm not convinced O2 enrichment is the
way to go. I have a chemist friend in the cacti/succulent world who has had
success using CO2 canisters to deliver foliar nutrients, and swears by it.
In most of lit I've read re: this application to orchids, there is an
optimal concentration for CO2 under which nutrients will be taken up by the
plants that is much lower than that used by my friend (somewhere around 30%
is the upper boundary depending on the species you are growing),
concentrations above this amount can eventually damage plants.
There were discussions back in march about the exact nutrients,
micronutrients, pH, etc. needed to sustain rapid growth in CO2 rich
environments.
As for hydrogen peroxide use, it is valuable (although in slightly higher
concentrations of 7-11%) in flasking and tissue culturing applications, and
I'm sure the 3% soln for repotting is probably a good anti-bacterial/fungal
precaution. One possible concern would be readsorption of excess salts,
but flushing with plenty of H2O should solve that.
Cheers,
S. Moore
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